Induction vapor or gas electric lamp.



P. G. HEWITT. INDUCTION VAPOR 0R GAS ELECTRIC LAMP.

APPLICATION FILED APE.18.1900.

Fig.1

PATENTED FEB. 5, 1907.

2 SHEETS-SHEET 1.

No. 843,533. PATENTED FEB. 5, 1907.

P. o. HEWITT. INDUCTION VAPOR 0R GAS ELECTRIC LAMP APPLIOATIOH FILEDAPB.18.1900.

, 2 SHEETSSHEET 2. F298 3 1 WW r termed an If there be substituted forthe 1 U r: i is srars;

. its enrich PETER COOPER HEWITT, OF NEW YORK, N. Y., ASSIGNOR, BY-MESNEASSIGN- MENTS, TO COOPER HEWITT ELECTRIC COMPANY, A CORPORATION OF NEWYORK;

mono-HON VAPOR os'eas ELECTRIC LAMP.

; Specification of Letters Patent.

Patented. Feb. 5, 1907..

.lpplication filed apriua'ieoo. seen Ho. 13.291.

To all whom it may concern: Be it known that I, PETER COOPER HEW- ITT,acitizen of the United States, and a re'si dent of New'York, in thecounty of New 5 York and State of New York, have invented certain newand useful Improvements in Inthe medium where the light is generated,the,

current beingwhat is known as a second ary current. v

The object'of my invention is to provide a lamp and-method of lightingwhich shall -y1eld a practical light without any conductor eading intothelamp, thus making it possible todispense with any break or joint inthe electric circuit. This accomplish by using .l a 5 vapor or gases ofproper character and under proper conditions as the medium fortransforming the electric energy into light, the energy being caused tobe present in the vapor or gases which serve as a conductor by Iinductiom- In this vway I dispense with conductorsleading into thecontained vapor or a gas through the walls'of the container.

1" It may be generally stated that a coil of traversed by a varyingcurrent of elec- 5 tricity is surrounded b a varying magnetic fieldconsisting ofso-ca ed magnetic lines I of force. -The field of forcethus established, however, varies in proportion with the variationsofthe current, and if a'closed 4o circuit-such, for instance, as a coilofwire '.be properly placed within this varying field ,of force therewill be induced in it a current; corresponding to the variations in thefield A device of this character is usually induction-coil 3 or transofforce.

former. secondary coil of the transformer a closed circuit of some vaporor gas of the roper character and under the proper conditions, it willact as a conductor,-and the energy of such current will be induced in itif therate of Change is suitable.

rentj will manifest'itself the form of light The energy of such cur-'and heat if sufiicient lines of force are cut by the vapor to overcomeits reluctance to become a conductor. 7

The induced current in the lamp and its ductionnamely, the relation ofthe turns in the primary to those in the secondary and the rate ofchange of the pulsations or variations in the actuating or primarycurrent, or, in other words, the rate at which the magnetic lines due tothe primary current are cut by the secondary circuit. This rate is thethe secondary circuit. In the form of lamp which I have devised it ispracticable to emin connection with a multiple-turn primary,

ormation. V

For the purpose of developing an electromotive force in the secondarysufficient to place it in a state where it will become conductor of lowresistance-Imake use of a current of such antity and rate of variationin a primary oi-such multiplicity of turns and such interlinkage as willinduce in one turn of a secondary an electromotive force which shall besuflicient to break down the tendency of the vapor to resist becoming aconductor notwithstanding the decrease of electromotive force which mustresult from the use of such multiple-turn primary as will give therequired interlinkage with the said vapor secondary.

use is that obtained frommercury, because of its low resistance;vbutother materials may be used, the use of any vapor bein .dependent onlyupon the requirement t at there shall be induced in it a voltagesufficient to overcome its resistance.,. Certain impurities or va orsadded to the vapors hich are selected for forming the secondary orlightemitting circuit exercise such a re the passage of the electriccurrent that it is .almostimpossible with the most rapid variation' ofcurrent to induce a secondary current in the lamp when they are present.Such vapors as will be obtained from water and some oxygen compoundsseem to have this lstate of non-conductivity in a marked deploy for thesecondary circuit a simple closed circuit of vapor having effectivelyone turn,

. iving a suitable ratio of step-dow n trans- The vapor which I findmost convenient in J voltage depend upon the general laws of inmeasureof the ele'ctromotive force given to readily conductive'that is, a truevapor uctance to will induce in a secondary of one turn an electromotiveforce of, say, from three to fifty volts per inch in case the secondaryis, say, three inches in diameter, the inducingcurrent need not be overa few hundred volts when the current is passing in the vapor, thevoltage depending upon the material of the vapor, its density, and otherconditions. The amount of light emitted by the gas read ily shows atwhat time during the process of manufacture the lamp is completed.

I am aware that others have proposed certain lamps claimed to beinduction-lamps having a luminous band induced therein; but in none hasany considerable amount of light been produced. -My lamp yields a largequantity of light and possesses other characteristics which clearlydistinguish it fromthe faint luminosity of the electrostatic effectproduced in the lamps above alluded to.

' The difference is also at once apparent in the source of current;

The invention will be described more in de- I cuit therewith.

3 is connected with the energizing-coil 1.

On the passage of a current of the proper character through the coil 3 acurrent is induced in the vapor. Immediately the vessel becomes brightlyluminous. position of the primary coil causes acorresponding change inthe position of the luminosity. By increasing the amount of en' A changein ergy imparted from the primary source practically all of the. vaporin the lamp may be made to act as a secondary andto give the lampa veryintense brightness. The addition of a second coil 4 on the globe of thevesthe coil 3 between them, and currents through this coil act upon thecontents of c both bulbs.

In Fig. 5 a modification is shown in which three bulbs 2 2 2- are shownarranged in close proximity to each other with coils 3 3 3 placedbetween them. These three coils may be connected in series or inparallel, as.

desired.

As already stated, the vapor which I find very convenient for use isthat of mercury. This vapor offers a low resistance and produces a veryintense white light. Other gases or vapors may, however, be used, carebeing taken toselect such as will receive current under the influence ofsuch .a voltage as may be induced'therein', and the light emitted.

thereby will-correspond to' the spectrum of that gas or vapor.

The 0 eration ofthe lamp depends upon the possibility of obtaining acurrent of suitable rate of variation. 1 have obtained excellent resultsby theuse of the dischargecurrents obtained from condensers; but aproperly-constructed Y mechanical generator would roduee the necessarycurrent. In F1gs8 Ihave represented diagrammatically one form ofapparatus giving a rapidlyvarying current suitable for use to o erate mylamp. This generator is indicate at 11 and reduces an alternatingcurrent of, say;

one undred and twenty-five to three hundred periods and of a voltage of,say, from fifty to one hundred -volts. he generator supplies the primarycoil 12 of a transformer, the secondary coil 14 delivering an' inducedcurrent .of, say,six thousand volt s. This induced current is deliveredto condensers 15 of suitable capaeity,'which maybe arranged to bedischarged through the line 16. I usu- IIO ally prefer, however, to usetwo condensers 1.5 15, as shown, using the current induced between themthrough the line 16; The 'discharge-gaps 17 limit the charge of thecondensers and serve to discharge them. d Other forms of dischargedevices may be employed-as, for instance, the well-knownvapor-dischargedevices disclosed in many of my early patents and applications. Eachl3 Qcurrent and" becomes brilliant, sealed off from the um time thecondensers are charged and discharged the current induced between themwill flow back and forth through the line 16. The current flowingthrough this line. is a rapidly-alternating current of considerablequantit' One of the glass vessels 2 being placed in the fieldof the coil3 will act as a secondary, tapping off the amount of current that thelamp is constructed to take.- The coil 3 thus becomes the'primary andthe vapor in the vessel the secondary, of my vapor transformer or lamp..With a pressure of six thounate the bulb. With'bulbs having otherchar-' acteristics the best number of termined by trial.

In manufacturing my lamp 1 usually proceed as follows: The lamp isconnected with an exhaust-pumpto remove the water and any vapors thatmaybe contained in the glass of the bulbfthe bulb being heated duringthe process of exhaustion. Lthen introduce or generate in the lamp thevapor upon which I desire to operate and which-is to act as thesecondary, still ret aining the connection with theexhaust-.pump,-usually introducing more of the vapor than it is intendedshall remain in the lamp when com leted.-. While still connected with.the e aust un'ip, I place a coil, such as the rimary'3, ig. 2,"ih suchposition that-its fie d may include the bulb and its inclosedvapor.There is then passed through this primary coil a rapidl varying current,and the effect upon t e vapor in the bulb is carefully noted. After theforeign and objectionable gases have been pumped out and the gas orzva'or which is to. be illuminated has reached t e- 'roperidensity thebulbreceives'the desire amount of- It isifthen and is finished. Thelight. produced y t lamp is'efn in-, tensely-luminouslight distinctionfrom the' foggy or hazy condition which may :be"pro-. duced by means ofelectrostatic-effect;'In the production of my lamps this foggy or hazyefiect is roduced during their reparation, usually uring the period ofe" austion before the density of the ultimate conducting-vapor has beenregulated and always in highly-rarefied gases with exceedingly rapid.

rate of variation'of the current obtained from the use -of smallcondensers and ye high voltage. This electrostatic effect usua ly ap- 1.

pears striated radially in aband in the tube, the striations appearinglike the open spaces in an ordinary carriage-wheel.

' In the production of the accompanied by a material change in theoperation of the system from that which '00- curs so long as' the foggyor hazy condition turns may be delamp herein 1 claimed theintensely-luminous condition-is system, the discharges of the spark-gapbeing accompanied by an'oscillatory action of the condenser-circuit butwhen the true conductive condition of the lamp as a secondary isreacheclthe oscillatory action of the-circuit practically ceases, owingto the fact that the secondary practically absorbs all the energy a infihe' action between the results obtained This true conl C i n may befurther demon- 'ofthe system at the first alternation of the.dise'harge. This emphasizes the difference ingthe methods heretoforeemployed in the ant and that obtained by me. sand volts and a bulb sixinches-in diameter a coil 3 of fifteen turnswill serve to illumistratedby bringing'the primary coil gradually into. closer relationship to thesecondary for lamp circuit and then gradually moving. it away. It=willbe found that the maximum luminosity of this conductive conditionof' 4 the secondarywill not a pear until the pri- -mary is brought into0 ose relationto the. lamp.

:' .The source 11 and the-secon'ary source device and not amereexperimental laboratory apparatus.- TheftermfVd'ynamic elec-wtricity and similar expressions as employed .j12 and 14, constitutingthe transformer, are Y of a character which adapts them to generatecurrents; of any desired quantity or electro- -motiveaforce, whereinthey differ: from the 1 proposedin conneb- 1 effects of inductionon-inclosed-gases-or vapor tricity, and this difference, among other,things,makes my lamp a practical operative ice here and'inthe claimsdenotes electricity in" 'current-form representing a flow rather than 5a static discharge whether the currentiis de- 10 5 rived from' adynamo-electric generator orf some other suitable source.

.- The invention claimed 19+;-

' -1. Agasor vapor'devicefconsisting ofan' Q inclosing chamber, agasoryapor containedtherein of such density and electrical resist- Irapidly-varyingelectric currents thr'oughthe primary, the'nuifiber. ofturnsof said coil and .the quantityand rate. of variation of said.

currents, being predetermined with respect tothe characteristics of saidgas or'yapor so I20 as to induce}.therein' currents 'of sufficientquantityto cause "said vapor to conduct'current inthe low-resistancecondition.

ing chain er, a primary ;exciting-coil, 'the rvapor or gas constitutingasecondary circuit for said rimary, theyapor or gas having such qua ityas to be tr'aversedby induced electric currents and absorb practicallyall the energy from an'oscillatorycircuit in the 2. ;A va or' or gasdevice having an inclosfiuence of said currents, means for transmitfirstoscillation, and means for transmitting raPidly-varyipg electriccurrents through the primary, thereby rendering the secondary luminous.

3, The combination of a gas or vapor havting rapidly-varying electriccurrents through said-primary coil, and thereby inducing currents in thesecondary, the length of the primary coil being so proportioned to theelectrical conditions of the circuit that variations in the currentflowing in the primary will be in direct proportion to the currentabsorbed by the secondary.

4. In a system of electric lighting, two or more primary coils connectedin parallel,gas

'- or vapor inclosing chambers in inductiveproximity to the respectiveprimary coils,

secondary circuits in the respective inclosing chambers consisting ofconducting vapor or gas of such density and resistanceas to co ductinduced currents under the influence o rapidly-varying currents suplying the 'respective primary coils, and t ereby inducing a flow ofcurrents in said secondaries, the priabsorbed in the secondaries.

mary coils and the source being so proportioned with reference to eachother and to the frespective secondaries that the currents flowingthrough the primaries shall vary in approximately direct proportion tothe currents 5. A source of rapidly-varying" electric currents ofapproximately definite quantity, and

a localized field actuated by said currents, in combination with aninclosed gas or vapor in inductive-relation to the field, the said gasor vapor having such a density and conductivity that it is adapted toabsorb practically all thee'nergy of said primary currents at each Ialternation;

' March, A. D. 1900.

6. A source of rapidly-varying electric currents of approximatelydefinite quantity, and a localized field to which said currents areapplied, in combination with an inclosed gas or vapor in inductiverelation to the field, the density and conductivity of the gas or vaporbeing specifically adapted to the applied currents so that the gas orvapor will become a low-resistance conductor andlight-radiant'by theelectromagnetic inductive eflect of said currents on said field.

7, The combination with a source of dynamic electricity, and means fortransforming the current into rapidly-varying current, a localized fieldto which said ra idly-varying currents are applied, a body 0 gas orvapor in said field of such volume, density, and conductivity, as toabsorb by electromagnetic induction, and to transform into heat, light,&c., all the energy of saidfieldate'achvariation of said currents.

8. The combination with an electric circuit carrying dynamic currents ofquantity, of means'for transformin the same into rapidly-varyingcurrents,'in ependent localized fields created by said rapidly-varyingcurrents, and an inclosed gasor vapor in each fieldof such volume,density, and conduc- .tivity as to be capable of absorbing the energypresent at each variation of the field.

9; The combination with an electric circuit'carrying dynamic currents ofquantity, of means for transformin the-same into rapidly varyingcurrents, in ependent localized fields created by said rapidly-varyingcurrents, an inclosed gas or vapor in each field of such density as tobe capable of absorbing and transforming into light the energy presoutat each variation of the field.

Signed at New York, in the-county of New York and State of New York,this 23d day of PETER COOPER HEWITT. Witnesses:

WM. H. CAPEL, OHARLESQB. HILL.

